In this study, we investigate the optical parameters of plasmonic Titanium Nitride (TiN) thin films using the RefFIT software, employing the Drude-Lorentz model for data fitting. TiN is an emerging material for plasmonic applications due to its high melting point, wear resistance, and stability at various temperatures, positioning it as a viable alternative to traditional noble metals. Our research focuses on fabricating, characterizing and extracting optical and electrical properties of TiN thin films deposited on silicon wafers using ellipsometry and Fourier Transform Infrared (FTIR) spectroscopy.We analyze six different samples, varying in thickness and composition, to determine key parameters such as plasma frequency and damping constants. The simultaneous fitting of reflectance and ellipsometry data in RefFIT provided results consistent with existing literature, establishing the software’s reliability for such analysis. Additionally, we validated the RefFIT results by comparing them with alternative models and experimental data, demonstrating the necessity of incorporating Lorentz terms alongside Drude components for accurate optical characterization.Our findings reveal that TiN films exhibit desirable plasmonic properties, with carrier concentration and relaxation times aligning with known trends in nitrides. The robustness of RefFIT in modeling these properties confirms its utility for future research in plasmonic materials. This study underscores the potential of TiN in advanced plasmonic devices and encourages further exploration using comprehensive modeling techniques.

This paper explores the design and analysis of planar multilayer Metal-Insulator-Metal (MIM) stacks as potential selective emitters for thermophotovoltaic (TPV) systems, specifically targeting medium-grade waste heat applications. These selective emitters are integral to TPV systems, which convert heat energy into electrical power. The study leverages the Transfer Matrix Method (TMM) to evaluate the optical properties of various MIM configurations, focusing on their absorption spectra. Materials such as Tungsten, Aluminum, Gold, Silver and Titanium Nitride were analyzed in combination with Hafnia as the dielectric layer. The results highlight that Silver/Hafnia and Gold/Hafnia stacks exhibit the most favorable narrowband absorption characteristics, matching the bandgap wavelength of Germanium converter cells. Additionally, Aluminum/Silica multilayer structures were optimized for different converter cells, showing potential in medium-grade heat recovery applications. The findings emphasize the importance of material selection and layer thickness in achieving high-efficiency TPV systems. By analyzing the spectral response, the study aims to optimize design parameters to enhance photon-to-current conversion and minimize energy losses in TPV cells.

This paper presents a comprehensive study on the design, analysis, and performance of Metal-Insulator-Metal-Insulator-Metal (MIMIM) multilayer stacks. The behavior of these stacks was modeled using the Transfer Matrix Method (TMM), allowing for a detailed investigation into their optical properties under varying parameters such as refractive index, layer thickness, polarization, and angle of incidence. The results highlight significant trends, including the effects of changing the incidence angle and layer thickness on reflection dips and absorption peaks, which exhibit wavelength-dependent shifts and intensity variations. These finding are particularly relevant for optimizing selective emitters in thermophotovoltaic (TPV) systems, where specific resonant peaks are desirable for efficient energy conversion. By adjusting the thickness of the metal and insulator layers, the study demonstrates how precise control over multilayer parameters can enhance performance, particularly through the strategic tuning of Fabry-Perot cavities within the stacks. The insights provided pave way for future applications in photonic and optoelectronic devices.